Powered tool transmission



1 R. s. SHORT ET AL 3,369,421

POWERED TOOL TRANSMI S S ION Filed Aug. 1, 1,966

FIGB

INVENTORS R S. SHORT PHIL D. THORP.

S WM

ATTORNEYS United States Patent Ofiice 3,369,421 POWERED TOOL TRANSMISSION R. Stanford Short, Bryan, and Phil D. Thorp, Montpelier, Ohio, assignors to The Aro Corporation, Bryan, Ohio, a corporation of Delaware Filed Aug. 1, 1966, Ser. No. 569,364 6 Claims. (Cl. 74-421) This invention relates to a powered tool and particularly one of the motor driven type having an elongated substantially flat gear train housing in the form of a projection to enter confined spaces, and having at its outer end means to rotate bolts, nuts, screws, and the like, or tools such as those used for. drilling, grinding, polishing, etc.

One object of the invention is to provide a tool which is particularly adapted for mounting on a motor housing and which has a housing-like arm in which a train of gears is mounted so that rotation imparted from the motor to a gear in one end of the housing results in rotation of an element in the outer end of the housing which is interiorly shaped to receive and rotate a shank of a wrench socket, flat screwdriver bit, Phillips screwdriver bit, Allen wrench or the like, or which may be designed to hold drills, reamers, and the like, thereby adapting the tool for operating fasteners or performing machining operations at comparatively inaccessible points such as locations inside of angles, channels and the like which are inaccessible.

Another object is to provide a tool which comprises a head element having means to secure the same to a .rnotor housing and adapted to receive a power shaft rotated by a motor in the housing, the gear train housing comprising a top plate, a bottom plate and an intermediate plate wherein the intermediate plate has within its outline a cavity for a plurality of intermeshing gears of a gear train.

Still another object is to provide the top and bottom plates with pintle receiving openings in which shouldered pintles are mounted so that when the top and bottom plates are assembled to the intermediate plate, the pintles are held against dislocation.

A further object is to provide the pintles with needle bearings for the intermeshing gears to rotate around, the

pintle at the outer end of the substantially flat elongated gear train housing having means for rotating some type of tool.

Still a further object is to provide the pintle at the inner end of the elongated gear train housing having a shouldered mount in the bottom plate of the housing and its upper end received in a socket of the head element.

An additional object is to provide means for mounting the elongated gear train housing on the head element by means of screws threaded into the head element and which hold the bottom plate assembled to the intermediate plate and the top plate against a fiat surface of the head element so that the gear train housing constitutes a rigid tool carrying an operating arm extending from the head element and the motor that drives the power shaft and thereby the gear train may be used as a handle for the tool.

Another additional object is to provide a head element for mounting on a motor housing which comprises a casting that can be machined to accommodate a gear train housing at any one of several angles relative to the motor housing.

With these and other objects in view, our invention consists in the construction, arrangement and combination of the various parts of our disclosed tool, whereby the ob jects above contemplated are attained, as hereinafter more fully set forth, pointed out in our claims and illustrated in detail on the accompanying drawing, wherein:

FIG. 1 is a perspective view of a powered tool em- 3,369,421 Patented Feb. 20, 1968 bodying our invention and showing it mounted on a motor housing;

FIG. 2 is an enlarged vertical sectionl view through our tool and an adjacent portion of the motor housing;

FIG. 3 is an up-side-down exploded perspective view of the bottom plate, intermediate plate and top plate which form the elongated gear train housing; and

FIG. 4 is a side elevation of a head element and illustrates how it may be machined for different angular relationships between the axis of a motor and a gear train housing which are operatively connected to the head element during assembly of the tool.

On the accompanying drawing we have used the reference character HE to indicate in general a head element, MH a motor housing and GTH a gear train housing. The motor housing MH may be made up of a motor shell 10 in which a suitable motor such as one of the pneumatic type (not shown) is mounted, and a shell 12 in which suitable step-down gearing is provided which terminates in a power shaft 14 shown in FIG. 2.

The head element HE has a flat lower surface 16 against which the gear train housing GTH is mounted as will hereinafter appear.

The gear train housing GTH comprises a top plate 18, an intermediate plate 20, and a bottom plate 22 which may be held together in assembled relationship by four small countersunk screws 24 and four large ones 26, one each of which is shown in FIG. 3. The plate 2%] acts as a spacer between the plates 18 and 22 and. cooperates with them to form a housing. Two dowel pin locaters 27 are also provided. Portions of the bottom plate 22 have been broken away to illustrate the screws 24 and 26 in FIG. 2. The screws 24 pass through the plates 22 and 20 and are threaded into the plate 18 while the screws 26 pass through all three plates 22, 20 and 18 and are screwed into the head element HE as shown dotted in FIG. 2.

The intermediae plate 20 has a cavity 21 to accommodate intermeshing gears. These gears comprise a gear 28 on a pin 40, five gears 29, 30, 31, 32 and 33 on five pintles 38, and a gear 34 on a sleeve-like pintle 36 journaled in holes 35 and 37 of the top plate 18 and the bottom plate 22 as shown in FIG. 2. The gear 28 rotates on a double needle bearing surrounding the pin 40 while the gears 29, 30, 31, 32 and 33 rotate on needle bearings surrounding the five pintles 38. The pintle 36 rotates in the holes 35 and 37 which serve as bearings therefor, and may be internally shaped other-than-round (such as hexagon or square) to receive the shank of a socket adapted for rotating bolts or nuts in the usual manner of a socket wrench. Obviously such shank may be on a screw driver bit, Allen wrench or any other special type of tool. Alternatively, the pintle 36 may be designed as a chuck or other holding device for drills, etc.

The lower end of the pin 40 is shouldered down to fit in a hole 46 of the bottom plate 22 to locate the lower end of this pin whereas the upper end is located in a socket 48 of the head element HE. Both ends of each pintle 38 is shouldered down to fit in holes 42 of the top plate 18 and holes 44 of the bottom plate 22 which arrangement enables ready assembly of the pintles and gears followed by retention of the gears between the plates 18 and 22 and the pintles against dislocation when the screws 24 and 26 are installed. This arrangement also retains the needle bearings in position. The top plate 18 is provided with an enlarged hole 54 to facilitate mounting of the gear 28, 52 on the needle bearings of the pin 40.

The gear 28 has integral therewith a bevel gear 52 which meshes with a bevel pinion 50 on the power shaft 14. Accordingly, rotation of the power shaft is imparted through the bevel gears and the train of gears 28-34 to the sleeve 36 whenever the motor in the shell MH is energized, thus rotating any socket that might be inserted into the sleeve 36 for tightening bolts, screws, nuts and the like, and likewise loosening them by reverse rotation of the motor and gear train.

The head element HE is provided with a pair of ears 56 and a clamp bolt 58 for clamping a cylindrical portion 60 of the head element on the step-down gearing shell 12 which is also cylindrical. The head element may be provided with a pair of ball bearings 62 for the power shaft 14 locked in position by a lock nut 64.

From the foregoing specification it will be obvious that we have provided a comparatively simple attachment for a pneumatic motor or the like in the form of a head element terminating in a substantially flat gear train arrangement capable of insertion into confined spaces for tightening and loosening fastening elements. The gear train housing is formed of flat plates Which are drilled, countersunk and tapped in such manner as to effectively journal a gear train and operatively connect the same through means of bevel gears in the head element to a power shaft of the pneumatic motor. Obviously, the tool disclosed can be likewise adapted for electric motors and the like. It can be used for nutsetting as well as many other purposes depending on the design of the pintle 36.

The gear train housing projects at an angle relative to the axis of the power shaft 14 but obviously, the head element HE may be so designed that the gear train housing can project parallel to the power shaft axis or at any other angle required for various specific jobs. If the gear train housing projects at 90 to the axis of the power shaft, it is merely necessary to provide a coupling between the power shaft and the gear 28 without utilizing bevel gears. FIG. 4 illustrates a head casting HE and shows how the face 16 may be machined at different angles to the motor axis such as 22, 60, and 90. Thus a single casting may be made into many different types of tools depending on the axis-to-gear train housing angle required.

Our disclosed structure provides for ease of manufacture by using simple parts instead of complicated parts and minimizes losses from machining errors common to complicated parts. It also combines strength and minimum dimensions where needed and the plates 18 and 22 providing structural strength. The flat gear train is unitized and readily replaceable for service of the tool, and angle heads can be produced from a single raw casting, most machined dimensions being common to all angle variations. The construction is extremely versatile and adapts very readily to mass production consideration.

The construction is also totally enclosed which affords advantages in lubrication, environmental cleanliness and extended service life.

Some changes may be made in the construction and arrangement of the parts of our powered tool without departing from the real spirit and purpose of our invention, and it is our intention to cover by our claims any modified forms of structure or use of mechanical equivalents which may reasonably be included within their scope.

We claim as our invention:

1. In a powered tool of the character disclosed, a head element having means to secure the same to a motor housing and adapted to receive a power shaft projecting from the motor housing and rotated by a motor therein, an elongated substantially flat gear train housing mounted on said head element and comprising a top plate, a bottom plate and an intermediate plate, said intermediate plate having within its outline a cavity for a plurality of interrneshing gears of a gear train, said top and bottom plates having pintle receiving openings, pintles therein, a gear on each pintle, the pintle at one end of said elongated gear train housing being adapted to rotate a tool, the gear surrounding said last mentioned pintle being secured thereto, and the gear at the other end of said gear train housing being operatively connected within said head element to said power shaft.

2. A tool in accordance with claim 1 wherein said operative connection comprises a bevel gear on said power shaft and a second bevel gear meshing therewith and connected with the gear at said other end of said gear train housing, said bevel gears being mounted within said head element.

3. A tool in accordance with claim 1 wherein needle bearings are provided on said pintles on which said gears rotate.

4. A tool in accordance with claim 1 wherein the means for mounting said gear train housing on said head element comprises a fiat surface on said head element against which said top plate is positioned, and fastening elements through said gear train housing and into said References Cited UNITED STATES PATENTS 871,939 11/1907 Kimman 74-421 2,302,853 11/1942 Gordon 74-421 2,709,923 6/1955 Manning 74421 DONLEY J. STOCKING, Primary Examiner.

L. H. GERIN, Assistant Examiner. 

1. IN A POWERED TOOL OF THE CHARACTER DISCLOSED, A HEAD ELEMENT HAVING MEANS TO SECURE THE SAME TO A MOTOR HOUSING AND ADAPTED TO RECEIVE A POWER SHAFT PROJECTING FROM THE MOTOR HOUSING AND ROTATED BY A MOTOR THEREIN, AN ELONGATED SUBSTANTIALLY FLAT GEAR TRAIN HOUSING MOUNTED ON SAID HEAD ELEMENT AND COMPRISING A TOP PLATE, A BOTTOM PLATE AND AN INTERMEDIATE PLATE, SAID INTERMEDIATE PLATE HAVING WITHIN ITS OUTLINE A CAVITY FOR A PLURALITY INTERMESHING GEARS OF A GEAR TRAIN, SAID TOP AND BOTTOM PLATES HAVING PINTLE RECEIVING OPENINGS, PINTLES THEREIN, A GEAR ON EACH PINTLE, THE PINTLE AT ONE END OF SAID ELONGATED GEAR TRAIN HOUSING BEING ADAPTED TO ROTATE A TOOL, THE GEAR SURROUNDING SAID LAST MENTIONED PINTLE BEING SECURED THERETO, AND THE GEAR AT THE OTHER END OF SAID GEAR TRAIN HOUSING BEING OPERATIVELY CONNECTED WITHIN SAID HEAD ELEMENT TO SAID POWER SHAFT. 